DerefOf probably doesn't work on `Object::Reference`

[martin-hughes]

Attempting to run the aml_tester against my machine's SSDT generated this error:

Error running test: ObjectNotOfExpectedType { expected: Reference, got: BufferField }

Taking a look at src/aml/mod.rs:808 onwards I can see the code expects a reference:

let result = if object.typ() == ObjectType::Reference {

But I don't think Object::typ() can return ObjectType::Reference - it recurses through to find the least innermost non-Reference object's type.

On my machine, the failing code is generating a reference to a buffer field - so Object::typ() is returning ObjectType::BufferField.

Unless I'm being daft, the code on line 811 (object.clone().unwrap_reference()) is unreachable.

[IsaacWoods]

Hmm nope I think the daft one is me - we should either have another variant of Object::typ (raw_typ or something) that does not unwind references, or just match the reference there manually.

Implementing DerefOf for index references correctly will likely require us to match against the reference kind anyways.

Happy to have a look when I get a chance or happy to accept a PR.

[martin-hughes]

I'm gradually building up to this, but as a relative newcomer to the crate the idea of dealing with references is still a little worrying - which is why I'm poking a lot of other stuff first. So if you get to it first - great! Otherwise I'll take a look at some point...